This invention relates to a power inlet arrangement for providing power to the electric system of a building, such as power supplied from a standby generator.
Portable generators may be used in certain situations to feed electrical power to residential and commercial load circuits during a utility power outage. These systems frequently include a power inlet box adapted for interconnection with the generator. The power inlet box is typically mounted to the exterior of a building. The power inlet box is connected to a transfer switching mechanism which continues the electrical path through circuit breakers associated with the transfer switching mechanism, to supply power to certain selected circuits of the load center as determined by the transfer switching mechanism circuit breakers. The circuits of the transfer switching mechanism are wired to selected circuits of the load center, through wiring housed within a conduit extending between the load center and the transfer switching mechanism.
The transfer switching mechanism includes a power input receptacle in its front face. Typically, the remote power inlet box is wired to a power cord connected to a junction box, which is engageable with the power input receptacle of the transfer switching mechanism.
It is an object of the present invention to provide a transfer switching mechanism which eliminates the need for a cord for providing input power to the transfer switching mechanism from a generator or power inlet interconnected with a generator. It is a further object of the invention to provide such a transfer switching mechanism which ensures that a reliable connection is established with the generator when power is supplied to the transfer switching mechanism. Yet another object of the invention is to provide such a transfer switching mechanism which is simple to install and which operates generally similarly to prior art transfer switching mechanisms.
In accordance with one aspect of the invention, a power transfer arrangement for supplying power from a generator to the electrical system of a building includes a power inlet arrangement for providing input power from a generator, in combination with a power transfer device separate from the power inlet arrangement and adapted for interconnection with the building electrical system. The power transfer device includes a power input terminal arrangement, and a direct electrical connection extends between and electrically connects the power inlet arrangement with the input terminal arrangement for providing a hardwired electrical connection between the power inlet arrangement and the power transfer device. The power transfer device preferably includes a cabinet, and the power input terminal arrangement is mounted within a power input terminal compartment defined by the cabinet. The power transfer device further includes a series of switches or circuit breakers for controlling the supply of power from the power transfer device to the building electrical system, and the series of switches are wired to the power input terminal arrangement. In one form, the power inlet arrangement is in the form of a remote power inlet box having a connector for receiving a plug to provide power to the power inlet box from the generator. The direct electrical connection between the power inlet arrangement and the power transfer device includes a set of power input wires, each of which has a first end connected to the remote power inlet box and a second end connected to the power input terminal arrangement. The set of power input wires preferably extend through a conduit having an end fixed to the cabinet such that a passage defined by the conduit, through which the power input wires extend, is in communication with the power input terminal compartment. The cabinet defines an opening providing access to the power input terminal compartment. A removable cover is positionable over the opening and removably engageable with the cabinet for selectively preventing access to the power input terminal compartment.
The invention further contemplates an improvement in a standby power supply system for connecting a generator to a power transfer device interconnected with the electrical system of a building, in combination with a power inlet remote from the power transfer device for connection to the generator to receive power from the generator. The improvement is in the form of a set of power input terminals provided on the power transfer device for establishing a direct electrical connection between the power inlet and the power transfer device. Details of the improvement according to this aspect of the invention are substantially in accordance with the foregoing summary.
Another aspect of the invention involves a power transfer device for interconnection with the electric system of a building including a cabinet, a set of switches or circuit breakers mounted to the cabinet, and a first set of wires for connecting the switches to an electrical distribution panel associated with the building electrical system. This aspect of the invention contemplates a terminal compartment associated with the cabinet and a set of power input terminals located within the terminal compartment. The power input terminals are electrically connected to the switches by a second set of wires. A set of power input wires extend into the terminal compartment and are adapted for a hardwired connection to the terminals for supplying power to the power transfer device. The power input wires preferably are interconnected with a remote power inlet box which is adapted for connection to the generator, such that power is supplied from the generator to the power inlet box and through the power input wires to the power input terminals.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.